PBBans

I downloaded Call of Duty 4 about 3 days ago and i have been trying to play some pro mod, but everytime i try and join i get kicked out giving me the message ...Restriction: Service Communication Failure: PnkBstrA.exe. I tryed uninstalling and reinstalling Punkbuster and Punkbuster is definatly turned on with the latest updates on Call of Duty 4. Help?

Try running pbsvc - this should install the missing pb files.
http://www.evenbalance.com/downloads/pbsvc/pbsvc.exe